Turbine well pump



Feb- 4, 1936. DE MONT G. MILLER TURBINE WELL PUMP Filed July 25, 1932 YIn v en for 2e Mont G. M/e'r Patented Feb., 4, 1936 PATENT OFFICE ATURBINE WELL PUMP De Mont G. Miller, San Marino, Calif., assigner toJohnston Pump Company,- Los Angeles',

Calif., a corporation of California Application July 25, 1932, SerialNo.,624,412

3 Claims. .(Cl. 10S-114) This invention has reference to deep wellturbine pumps, either of the extensible line shaft or submersed motordriven types, the principal objects of the invention being directed toimprove- 5 ments whereby the operating efficiencies of such pumps maybematerially increased over the eflciencies heretofore obtainable, andwhereby the useful life of such pumps may be substantially prolonged.

l One ofthe factors tending to lessen the operating eiiiciency ofturbine well pumps, is fluid friction loss in the submersed pump proper,that is 'Within the series of bowls in which impellers are carried onthe pump shaft. Where the interior l surfaces of the bowls and theimpeller surfaces are left rough, a substantial amount of the powerinput to the pump is takenup in overcoming q friction losses between thepump parts and the well liquid being discharged upwardly through i 20the pump to the ground surface. Itis customary to reduce such frictionlosses by special operations on the pump bowl castings, as bysandblasting or otherwise smoothing their interior Surfaces. Theimpeller surfaces are made smooth by machining operations, and byforming the impellers, in some instances, of bronze, which presents asmooth surface, but which, incidentally, is comparatively expensive.

It is a universal practice and neccessity in'mak- 30 ing the pump partsas castings, to subject them to special operations for smoothing theirliquid contacting surfaces to lower frictional losses within permissiblelimits; and prior to the present invention, it has not been practical touse comparatively rough surface castings without the necessity foriinishing operations.

I may also mention that experience has indicated that after a. pump hasbeen in operation in the well over a considerable period of time, theparts become subject to deterioration as a result of galvanic action oflthe well liquid, particularly in water wells carrying minerals tendingto promote such action. Also the pump parts are continuously subjectedto great wear as a result of erosion by abrasive particles, usuallysand, carried in the well liquid and discharged through the pump atVhigh velocities.

In accordance with the invention, frictional losses are reduced to a lowminimum and deterioration of the pump parts as a res'ult of the agenciesabove noted, are prevented, by a vitreous enamel or porcelain coatingapplied to the pump parts by fusing the coating into the metal. Sosmooth is the surface of the enamel, as compared 55 to that of theuncoated metal, that Very n iate.-

rial reductions in friction losses may be attributed to the applicationof the vitreous coating, 'the latter having a coecent of frictionapproximately the same as that of glass. To illustrate the increase inthe over-all operating em- 5 ciency of the pump, as the result ofvitreous coating being applied to the impellers and bowl interiors, itmay be mentioned that in one test, a pum'p normally operating with aneiciency of '74%, was increased in eiiiciency to 79%. 10

Deterioration as a result of galvanic action is completely overcome,since the exposed surfaces of the pump parts are coated with a vitreousenamel not subject to attack by galvanic action. Wearing of the parts asa result of the abrasive action of sand particles carried in the wellliquid, is also relieved from serious consequence inasmuch as the enamelpresents a hard surface extremely resistant to abrasive wear.

The invention will perhaps be more fully understood from the followingdetailed description, throughout which reference is made to theaccompanying drawing.

In the drawing there is shown a fragmentary sectional .view of a typicaldeep well turbine pump. While for purposes of illustration I have showna particular type of pump construction, it will be understood that suchshowing is illustrative only, and that the invention is applicable toall types of deep well turbine pumps, irrespective of particularities asto structure.

The pump body includes a series of pump bowls l0 which are joinedtogether by screws II, there being attached to the lower. bowl by screwsI 2, the usual suction nozzle I3, the details of which it will not benecessary to describe. Each of the bowls comprises an outer shell I 0aand an inner concentric tubular core Illb cast integrally with the outershell by way of circularly spaced radial ribs I4. Suction nozzle I3 issimilarly formed 40 with a central tubular core I3b within which theshaft journaling bushing I5 is inserted. A similar bushing I6 journalsthe shaft I1 Within the bore of core Ib of the pump bowl. The pumpf ingelements comprise impellers I8, keyed to shaft I1, and contained withinimpeller chambers of the bowls I0, the impellersbeing of the usual typehaving upwardly extending radial passages 2U between ribs 2|. Thestructural characteristics of this type of pump are so commonly knownthat no further description of details will be required forpresentpurposes.

In the operation of the pump, shaft I'I and the impellers I8 arerotatively driven by a motor, not shown; connected to the shaft, wellliquid being .55

tion nozzle and discharged upwardly by the series of impellers throughpassages 23 in the pump bowls, and finally into the usual eduction pipelleading to the ground surface.

The surfaces of the impellers I8, includinggthe surfaces of ribs 2|, areshown to be coatediyith vitreous enamel 24. .Similar vitreous coatings24 are applied to the interior of the bowls, including ribs I4, and alsoto the exterior surfaces thereof, if desired. It will be understood thatin the broad aspects of the invention, the impellers alone, or the bowlsalone, may be given the vitreous coating, since such coating applied toeither of the elements will effectively increase the operating eiciencyof the pump. However,'it will generally be best to apply the vitreouscoating to all the parts, to the end that the highest working efficiencypossible will be obtained, and all surfaces .willbe protected fromgalvanic action or wearing away by abrasives. Thus, as shown in thedrawing, the enamel coatings may preferably cover all or substantiallyall the interior surfaces of the bowl, including its internal uidpassages; and all or substantially all the impeller surfaces, bothinternal and external. This may include the surfaces, for instance, VatA and B where the bowl and impeller closely interfit to prevent leakage,or at such points the enamelling may be omitted. Thus the drawingindicates omission of the enamel at such points on one or the other ofthe bowl and runner. It is desirable that the whole of the runner beenameled, except perhapsA at the points of close approach to the bowl,as all other surfaces of the runner are moving at high speed in thewater. And for similar reasons it is desirable although not soimportant, to coat all or most of the interior surfaces of the bowl.

As previously mentioned, by applying such vitreous coating to the pumpparts, the latter may be made from less expensive and comparativelycoarse grained metals which, in the absence of the vitreous coating,would require machining operations and hand-work to reduce theirsurfaces to the necessary smoothness. It has been found that thevitreous enamel, when in a fused state, lls in the surfaceirregularities of the metal and hardens to present surfaces ofglass-like smoothness. This is due to the fact that although applied torough or irregular surfaces, the fused vitreous enamel has a surfacetension which causes the exposed surfaces of the enamel to harden to anextremely smooth finish.

From the drawing it can be seen that the bowl and impeller are formed,in the main, each from a single casting in contrast to the built-uptypes of pumps. When the bowl and impeller are each cast in a singlepiece, the water passages are relatively inaccessible, because of theirsm'all size andtheir tortuousness, so that it becomes very diflicult toproduce smooth surfaces on the walls of these passages.

The only manner in which irregularities on the inner surface of the pumpbowl castings may be removed, is by a sand blasting operation. However,sand blasting is effective only to remove loose irregularities adheringto the inner surfaces of the bowl castings, and is ineffective to rendersuch surfaces smooth Where irregularitiesother than comparatively looseparticles, occur in the castings. .'Ihus, heretofore, because of theinaccessibility of the interior parts of the bowl castings, it has beennecessary to allow such surface irregularities as could not be removedby sand blasting, to remain. The advantages and utility of the presentinvention become apparent upon considering the fact that by applying thevitreous enamel to the interior surfaces of the castings. these surfacescan be given a smoothnessheretofore unobtainable by any operationnotwithstanding the inaccessibility of the surfaces; since the coatingsmay be dipped in the enamel solution and the coating hardened by baking.

'I'he same may be said to be true of the interior passages within theimpellers. The only practical manner in which it has heretofore beenpossible to smooth the interior Walls of the impellers, is by costlyhand-work, requiring considerable time. By the provisions of theinvention, the interior surfaces within the impellers can be givenglasslike smoothness by the vitreous coating,'to the exclusion ofhand-work heretofore required.

Sandblasting provides a clean surface to receive the enamel, and thoughother methods of cleaning may be used, Sandblasting is most effective asit reaches all parts of the inaccessible surfaces. Such cleaning ofadhering matter is necessary to the proper formation and adhesion of theenamel to form a regular, smooth and lasting surface. f

By virtue of the smoothness of the enameled surface, the frictionalresistance to the flow of well liquid through the pump is reduced to afar lower minimum than would be possible in the case of metallic surfaceparts, even though they be specially machined or sand blasted to smooththeir surfaces to the greatest extent.

I claim:

l. In a deep-well turbine pump structure suitable for pumping watercontaining abrasive material from a Well, the combination of: a castingforming a bowl element positioned in an inaccessible position in saidwell beneath the surface of said water and providing passages forconducting said water upward, portions of said passages beinginaccessible for smoothing, said bowl element providing an impellerchamber, said impeller chamber and said passages being coated withporcelain fused directly to clean irregular surfaces of the casting toform a hard abrasive-resistant smooth surface guiding a highvelocitystream of said Water; a shaft extending into said impeller' chamber; anda casting form'- ing an impeller in said impeller chamber and providinganupper shroud and a lower shroud and vanes extending therebetween toprovide impeller passages relatively inaccessible for smoothing, thewalls of said impeller passages being coated with porcelain contactingand fused directly to a clean irregular surface of the casting Vformingsaid impeller to form hard abrasive-resistant smooth surfaces throughwhich said water moves at high velocity, the outer edges of said vanesand the exterior surface of said upper and lower shrouds being alsocoated by said porcelain adhering to clean irregular surfaces of saidcasting.

2. In a deep-well turbine pump structure suitable for pumping watercontaining abrasive material from a well, the combination of: a castbowl means positioned in an inaccessible position in said well beneaththe surface of said .water and providing passages for conducting saidwater upward, portions of said passages being inaccessi-V ble forsmoothing, said bowl means providing an impeller chamber, said impellerchamber and said. passages being coated with porcelain fused directly toclean irregular surfaces of the casting to form a hardabrasive-resistant smooth surface ly to a clean irregular surface ofthecasting forming said impeller to form a hard abrasive-resistantsmooth surface through which said water moves at high velocity, theexterior surfaces of said upper and lower shrouds being also coated bysaid porcelain adhering to clean :irregular surfaces of said casting,said impeller means providing a skirt portion with an external surfaceextendingin close proximity to a corresponding portion of said bowlmeans,the porcelain coating on at least one of said means terminatingshort of said portion which is in proximity to the other adjacentportion whereby at lestone of thesev adjacent portions provides nocoating of porcelain thereon.

3. In a deep-well turbine pump structure suitable for pumping watercontaining abrasive material and minerals from a well; the combinationof: a cast' bowl means positioned in an inaccessible position in saidwell beneath the surface'of said water and providing high-velocitylinternal passages of relatively restricted crosssectional areas forconducting said water upward, portions of said passages beinginaccessible for smoothing, said cast bowl means providing an impellerchamber; a shaft extending into said impeller cham,

ber; an impeller casting providing a central openingr Ythrough whichsaid shaft extends and forming an impeller fitting rotatably within saidcast bowl means in said impeller chamber and having certain limitedsurfaces at which it closely approaches complementary interior surfacesof said bowl means to restrict leakage of fluid past said impeller, saidimpeller casting providing high-velocity internal passages of relativelyrestricted cross-sectional areas discharging into said internal passagesof said bowl means; a coating of porcelain fused directly to the cleanrough surfaces of said impeller casting andcovering the exterior surfacethereof in those which do not closely approach said bowl means butterminating exterior of said central shaft-receiving opening whereby thewalls of said; central opening are uncoated by said porcelain, saidcoating also covering the whole of the wall surfaces of said internalfluid passages of said impellercasting; and a coating of porcelainsimilarly applied directly to the clean rough surfaces of said bowlmeans bounding said impeller chamber and said high-velocity internalpassages lof said bowl means, said coatings of porcelain covering andsubmerging all minor irregularities of said clean rough surfaces of saidcastings and entering the irregularities thereof tov increase the bondbetween said coatings and said castings to withstand contact with thehigh-velocity pumped liquid' and to withstand high centrifugal forcesdeveloped by rotation of said impeller casting. said coatings beingformedV of material more resistant to abrasion by said water than saidcastings and presenting smooth surfaces for guiding said water with

